215142481 has 2 divisors, whose sum is σ = 215142482. Its totient is φ = 215142480.

The previous prime is 215142451. The next prime is 215142493. The reversal of 215142481 is 184241512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139452481 + 75690000 = 11809^2 + 8700^2 .

It is a cyclic number.

It is not a de Polignac number, because 215142481 - 2²³ = 206753873 is a prime.

It is a super-2 number, since 2×215142481² = 92572574261670722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (215142401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107571240 + 107571241.

It is an arithmetic number, because the mean of its divisors is an integer number (107571241).

Almost surely, 2^215142481 is an apocalyptic number.

It is an amenable number.

215142481 is a deficient number, since it is larger than the sum of its proper divisors (1).

215142481 is an equidigital number, since it uses as much as digits as its factorization.

215142481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2560, while the sum is 28.

The square root of 215142481 is about 14667.7360557108. The cubic root of 215142481 is about 599.2049478781.

Adding to 215142481 its reverse (184241512), we get a palindrome (399383993).

The spelling of 215142481 in words is "two hundred fifteen million, one hundred forty-two thousand, four hundred eighty-one".